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901.
Suicide rates are higher at high altitudes; some hypothesize that hypoxia is the cause. We examined 8,871 suicides recorded in 2006 in 15 states by the National Violent Death Reporting System, with the victim's home county altitude determined from the National Elevation Dataset through FIPS code matching. We grouped cases by altitude (low<1000m; middle=1000-1999m; high≥2000m). Of reported suicides, 5% were at high and 83% at low altitude, but unadjusted suicide rates per 100,000 population were higher at high (17.7) than at low (5.7) altitude. High and low altitude victims differed with respect to race, ethnicity, rural residence, intoxication, depressed mood preceding the suicide, firearm use and recent financial, job, legal, or interpersonal problems. Even after multivariate adjustment, there were significant differences in personal, mental health, and suicide characteristics among altitude groups. Compared to low altitude victims, high altitude victims had higher odds of having family or friends report of a depressed mood preceding the suicide (OR 1.78; 95%CI:1.46-2.17) and having a crisis within 2weeks before death (OR 2.00; 95%CI:1.63-1.46). Suicide victims at high and low altitudes differ significantly by multiple demographic, psychiatric, and suicide characteristics; these factors, rather than hypoxia or altitude itself, may explain increased suicide rates at high altitude.  相似文献   
902.
Rating scales are often used to measure behavioral constructs. Yet, different informants’ ratings may not necessarily agree. The situational specificity (SS) perspective postulates that discrepancies between ratings by different informants are primarily attributable to contextual behavior of the people being rated. The multitrait-multimethod (MTMM) perspective, however, attributes discrepancies between informants to rater bias, i.e., each informant provides a systematically distorted picture of the person being rated. Similarly, the Attribution-Bias-Context (ABC) perspective also attributes informant discrepancies to systematic biases. Within the context of measuring hierarchical constructs, we proposed a hybrid perspective that takes account of variance attributable to the behavior of the person being rated in a particular context from the perspective of a specific informant. We then provided a parametric representation of this perspective and analyses of mother, teacher, and self-ratings of Rule-Breaking and Aggressive Behavior to illustrate features of the model. Strengths and limitations of the SS, MTMM, and hybrid perspectives are discussed.  相似文献   
903.
Using social capital theory as a framework, the authors examined data from the Educational Longitudinal Study of 2002 (Ingels, Pratt, Rogers, Siegel, & Stutts, 2004) to investigate how student contact with high school counselors about college information and other college‐related variables influence students' college application rates. In addition to some college‐related variables, the number of school counselors and student contacts were significant predictors of college application rates. Implications for school counselors and counselor training are included.  相似文献   
904.
In the research reported here, we examined whether processing speed mediates the development of general intelligence (g) in adolescence. Using the Armed Services Vocational Aptitude Battery, a battery of 12 diverse cognitive tests, we assessed processing speed and g in a large sample of 13- to 17-year-olds obtained from the National Longitudinal Survey of Youth (N = 6,969). The direct effect of age on g was small compared with the total effect of age on g, which was almost fully mediated through speed. The results suggest that increases in g in adolescence can be attributed to increases in mental speed.  相似文献   
905.
Using conservation of resources theory as a guide, this study examines why individuals with an internal locus of control (LOC) are more likely to feel embedded in their organizations. Two mediating processes are posited. First, people with high internal LOC are more likely to acquire greater work resources because they are more effective in negotiating and receiving employment deals which are not widely available or replicable elsewhere. Second, people with high internal LOC are more likely to acquire additional work resources because they network more proactively with colleagues and supervisors. Consequently, high LOC individuals are likely to become more embedded because they have more links with their colleagues and the sacrifices associated with leaving their jobs would be greater. The proposed model was tested and supported with three waves of data collected from a sample of 375 managerial respondents over an 8‐month period. Implications for future research, especially the role of personality traits in understanding organizational embeddedness, are also discussed.  相似文献   
906.
The two‐step flow model of communication (Katz, 1957 ) suggests opinion leaders obtain critical information from the mass media and, in turn, communicate this information to interpersonal contacts such as friends, family and co‐workers. It is suggested that religious leaders (RLs) may serve as opinion leaders on the topic of organ donation by debunking donation myths, promoting donation during worship services, or communicating the benefit of donation to families faced with the opportunity to participate in living or cadaveric donation. The current study examined the personal knowledge, experiences, and willingness to communicate about organ donation in a sample of RLs (N = 59) in Rochester, New York. Structured interviews were conducted in summer and fall of 2009 with a random sample of RLs. Results indicate a disparity between RLs' expressed personal support for donation and their engagement in donor registration. Approximately one‐quarter of RLs have spoken about donation during a religious service and many indicate their knowledge is not sufficient to discuss organ donation in detail. Results elaborate on how RLs may be trained to serve as opinion leaders in the promotion of organ donation. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
907.
Research among African-Americans indicates this population perceives sickle cell (SCD) to be a serious disease and sickle cell trait (SCT) screening an important intervention. However, studies have consistently demonstrated a lower than desired uptake of SCD education, inadequate knowledge regarding personal and family trait status, and a low perceived susceptibility of giving birth to a child with the disease. We examined general attitudes and beliefs regarding genetics and genetic testing including prenatal testing and newborn screening; we used this information as the foundation to more specifically assess attitudes and beliefs regarding SCD and perceived barriers to SCD education and awareness. Thirty-five African-American adult men and women participated in one of four focus groups. Thematic analysis identified that both prenatal testing and newborn screening are acceptable forms of genetic testing. Based largely on their personal experiences, participants possessed an understanding of the natural progression of SCD but had a limited understanding of the inheritance and probable risk of giving birth to a child with the disease. Barriers to education and greater awareness of SCD were classified as personal, familial, and societal. Community based interventions focused on sharing the stories of individuals with first-hand experiences with SCD should be considered.  相似文献   
908.
909.
5-bromo-2-deoxyuridine (BrdU) is often used in studies of adult neurogenesis and olfactory learning, but it can also have toxic effects on highly proliferative tissue. We found that pairing Kool-Aid flavors with acute systemic injections of BrdU induced strong conditioned flavor aversions. Intermittent injections during Kool-Aid-glucose conditioning interfered with learning of a conditioned flavor-nutrient preference. Acute injection of BrdU also elevated plasma corticosterone levels and induced c-Fos in the visceral neuraxis. Thus, acute or intermittent systemic injections of BrdU (50-200 mg/kg) have aversive effects that may interfere with learning.  相似文献   
910.
Thomas Filk 《Axiomathes》2011,21(2):221-232
A violation of Bell’s inequalities is generally considered to be the Holy Grail of experimental proof that a specific natural phenomenon cannot be explained in a classical framework and is based on a non-boolean structure of predications. Generalized quantum theory allows for such non-boolean predications. We formulate temporal Bell’s inequalities for cognitive two-state systems and indicate how these inequalities can be tested. This will introduce the notion of temporally non-local measurements. The Necker-Zeno model for bistable perception predicts a violation of these temporal Bell’s inequalities.  相似文献   
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